Fewer students from pre-kindergarten to fourth grade took the private-school entrance exam this school year, compared to last year, according to data compiled by the testing service.

An estimated 4,418 students took the test, known as the ERB, for the 2011-12 school season, while an estimated 4,245 took it this year — a 4 percent decrease.

Experts said the dip gives students a better chance at getting into second-tier schools because there is less competition, said education consultant Dana Haddad, an ex-admissions director at Horace Mann.

But she warned the decline doesn’t affect top-tier schools — like Chapin, Dalton, Riverdale, Brearley or Trinity — because they will always have too many applicants.